The steam jet ejectors are pumps that mix or compress many different fluids.
 
They have no moving parts and operate by the action of one high pressure stream entraining air and 
other vapours (or liquids) at a lower pressure into the moving stream and there by removing them from 
the process system at an intermediate pressure higher than the suction pressure but many times lower 
than the motive steam pressure.
 
The main components of the steam jet ejectors are: the nozzle, the suction and mixing chamber, the diffuser.
 
For the reason listed before steam jet Ejectors have the following features which make them good choices for 
continuously producing economical vacuum conditions:
 
1. They handle wet, dry or corrosive vapor mixtures.
2. They develop any reasonable vacuum needed for industrial operations.
3. All sizes are available to match any small or large capacity requirements.
4. Their efficiency is reasonable-to-good.
5. They have no moving parts, hence maintenance is low, and operation is fairly constant when corrosion is not a factor.
6. Quiet operation.
7. Stable operation within design range.
8. Installation costs relatively low when compared to mechanical vacuum pumps. Space requirements small.